Dan, I know you posted this awhile ago. I am just in the process of setting up a cnc router and a separate laser. The answer you gave was so helpful as I have never done cnc before. Could anyone tell me if I can use black walnut, that has only been dried for one year, to use for routing or laser? Thank youDan, walnut, cherry and maple cut well and are good for most projects as you have found and can be found for a decent price. The important thing is to make sure they are not something freshly cut from a sawmill. They do need to be well dried to get good results for CNC use. Actually, each and every board can present anywhere from great carves with very little cleanup to poor carves with a lot of cleanup time involved.
Construction grade lumber might be kiln dried but not to the same levels as hardwood lumber. It is also softwood and tends to cut poorly, often leaving a lot of strings and small tear-outs. I don't even recommend it for test cuts.
When you get into the hard exotic woods, some like wenge can pose a problem if using dull bits or bits with the wrong geometry. Wenge is often dry and brittle and tends to split but when cut but using sharp tooling will need very little cleanup. It is a good wood to use if you are looking for a very dark to black color but can often hide fine detail because of the dark color. It is a good wood to use for contrasting on-lay work.
Then there are heavy, hard exotics like Cocobolo, normally very high in cost, that contain a lot of oils. Projects are almost polished when cut, brush off the dust and chips and it is ready for finish. I love using it for small intricate 3D carves but can't justify the cost for medium and large projects.
I think the biggest consideration when picking wood for CNC use is the cost.
If you are just a hobbyist and hang most of your projects on your own walls then you might want to branch out and use anything you see that catches your eye for one reason or another. You might like the color or maybe some really squirrely grain of some exotic burl. Or you might be trying your hand at Intarsia type projects where you mix a lot of different colors and grain patterns for your project. It is different if you are giving you projects away to family and friends, I'm talking about the everyday experiments and test cuts you make, not projects you make for special occasions.
If you give away a lot of projects then you might want to consider the cost of the wood you use. Choose something decent that cuts well so cleanup doesn't take forever and make the project a pain in the neck, instead of a fun to make gift.
If on the other hand, you are making projects to sell, you will want to use expensive exotics and burls only as small projects like jewelry or separate elements of larger projects. That brings you back to the standard native woods that are readily available and affordable. You don't have to buy wood from a store or reputable mill you can often find table leaves or whole tables at garage sales that make blanks for project. Don't pass up an old dresser made from hardwood that needs work, pull it apart, and use the parts for projects. If you have the room to store it and equipment to process raw lumber then you might consider that free choice of project wood.
The big thing to remember is to use sharp tooling and don't be afraid to test cut new-found materials, you might find a new favorite wood or material.